Process and catalyst for production of olefin polymers



United States Patent PROCESS AND CATALYST FOR PRODUCTION OF OLEFIN POLYMERS No Drawing. Application December 30, 1955 Serial No; 556,484

19 Claims. cl. 260-949) This invention relates to the polymerization of olefins. In one aspect, this invention relates to an improved method for polymerizing olefins and to a novel catalyst therefor.

Reactions for polymerizing olefins are well known in the art and are generally carried out in the presence of catalysts. One type of catalyst which has been used in the polymerization of monoolefins, particularly ethylene, consists of oi'ganometal compounds, for example triethylaluminum, and the polymers whichhave been obtained in accordance with this method are generally liquid or low molecular weight solid polymers. Frequently, the polymers obtained are dimers or trimers of the olefin charged. However, it is often desired toproduce higher molecular weight polymers which have desirable properties of heat stability and can be molded into vessels, pipes and tubing. Such uses cannot be made of the lower molecular weight polymers, for example, a polymer having a molecular weight of about 1000, since a polymer of this molecular weight is a wax-like material.

It is an object of this invention, therefore, to provide an improved process for the production of high molecular weight olefin polymers.

A further object is to provide a novel catalyst foruse in the production of olefin polymers.

A still further object is to product high molecular weight solid polymers of olefins, such as ethylene.

Gther and further objects and advantages of this invention will become apparent to those skilled in the art upon consideration of the accompanying disclosure.

it has now been discovered that an unexpected improvement in the production of high molecular weight polymer is obtained when an olefin, such as ethylene, is polymerized in the presence of a catalyst composition comprising (1) a metal halide selected from the group consisting of halides of titanium, zirconium, hafnium and germanium, (2) a compound selected from the group consisting of carbides corresponding to the formula M c, and acetylenic compounds corresponding to the formula M-(CECR) wherein M is a metal selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, magnesium, barium, strontium,calcium, zinc, cadmium, mercury, copper, silver and gold, wherein R is selected from the group consisting of hydrogen,- an alkyl, cycloalkyl, or aryl radical or combination of these radicals, wherein a equals 2 when the valence of themetal is 1 and wherein a equals 1 when the valence of the metal is 2, and wherein b is equal to the valence of the metal, and (3) at least one component selected from the following: (a) an organometal halide corresponding to the formula R MX wherein R is a saturated acyclic hydro carbon radical, a saturated cyclic hydrocarbon radical, an aromatic hydrocarbon radical, or combination of these radicals, wherein M is a metal selectedfrom the group consisting of aluminum, gallium, indium, thallium, and beryllium and wherein X is a halogen, andwherein x and y are integers, the sum ofjc and y being equal m valence of "ice the metal; (b) a mixture of an organic halide and at least one metal selected from the group consisting of sodium, potassium, lithium, rubidium, cesium, beryllium, magnesium, zinc, cadmium, mercury, aluminum, gallium, indium and thallium; and (c) a complex hydride corresponding to the formula MMH wherein M is an alkali metal, M'" is a metal selected from the group consisting of aluminum, gallium, indium and thallium, and m is equal to the" sum of the valences of the two metals. The prove'ment obtained when polymerizing" an olefin in the presence of our novel catalyst is, firstly, that polymers of much higher molecular weight possessing very high impact strength and other desirable characteristics can be obtained than is true when certain of the prior art cataly'sts have been employed, and secondly, the polymerization reaction, particularly for ethylene, can beinitiated and carried out at considerably lower temperatures and pressures thanare necessary when employing the catalysts and the processes of the prior art. 7

The metal halide component of our catalyst system comprises the halides of the metals titanium, zirconium, hafnium and germanium. Examples of metal halides whichcan be used include titanium dichloride, titanium trichloride, titanium tetrachloride, titanium dibromide, titanium tribromide, titanium tetrabromide, titanium diiodide, titanium triiodide, titanium tetraiodide, titanium trifluoride, titanium tetrafiuoride, zirconium dichloride, zirconium trichloride, zirconium tetrachloride, zirconium dibromide, zirconium tribromide, zirconium tetrabromide, zirconium tetraiodide, zirconium tetra fluoride, hafnium trichloride, hafnium tetrachloride, hafnium triiodide, hafnium tetraiodide, germanium dichloride, germanium trichloride, germanium tetrachloride, germanium dibromide, germanium tetrabromide, germanium diiodide', germanium tetraiodide, germanium difluo ride, germanium tetrafluoride and the like. Mixtures of two or more of the metal halides can be employed in the catalyst system of our invention.

In admixture with one or more of the metal halides describedabove our novel catalyst comprises a compound selected from the group consisting of carbides corre= spending to the formula M C and acetylenic' compounds corresponding to the formula M'--(C'ECR) wherein M is amet'a'l selected from the group consisting of lithiurn, sodium, potassium, rubidium, cesium, magnesium, barium, strontium, calcium, zinc, cadmium, mercury, copper, silver and gold, wherein R is selected from the group consisting of hydrogen, an alkyl radical, a cycloalkyl radical, an aryl radical and combinations of these radicals, wherein a equals 2 when the valence of metal M is l and wherein a equals 1 when the valence of metal M is 2, and wherein b is equal to the valence of metal M. It is preferred that each of the aforementioned'radicals' which can be substituted for R in the formula contains not more than 10 carbon atoms. Mixtures of two or more of these compounds can be used in our catalyst composition. Examples of carbides and acetylenic compounds which can be utilized include lithium carbide, sodium carbide, potassium carbide, rubidium carbide,- cesium carbide, calcium carbide, barium carbide, strontium carbide, magnesium carbide, zinc carbide, mercure ous carbide, mercuric carbide, cuprous carbide, silver carbide, gold carbide, sodium acetylide, potassium acetyl= ide, cesium acetylide, l-hexynylsodium, Z-phenylethynylpotassium, di(l dodecynyl) calcium, di[l (5 cyclo hexylpentynyl)]barium, l 3 methylbutynylJmercury, di[l-(4-phenylhexynyl) lzinc, di[2 cyclopentylethyny-llmagnesium, 5,6 dimethyldecynylcopper, and' the like.- With regard to the carbides and acetylides used in our catalyst system, it is noted that in the literature these terms are in some cases used interchangeably. For example, Na c is sometimes described as being sodium pounds, such as Li C or CaC which correspond to the formula- M C as defined above. The termacetylide on the other hand is reservedfor compounds, such as '(CECR.);, in which R is hydrogen.

NaHC or KHC which correspond to the formula In admixture with at least one of the metal halides and at least one of the carbides and/or acetylenic compounds'as set forth above our catalyst comprises at least one organometal halide corresponding to the formula R MX wherein R is a saturated acyclic hydrocarbon radical, a saturated cyclic hydrocarbon radical, an aromatic hydrocarbon radical, or mixtures of. these radicals,

'wherein M is a metal selected from the group consisting of aluminum, gallium, indium, thallium and beryllium,

and wherein X'is a halogen. The xand yare integers and the sum of x and y is equal to the valence of the metal M. X can be any of the halogens, including chrine, bromine, iodine and fluorine. The saturated acyclic hydrocarbon radicals, saturated cyclic hydrocarbon radicals, and aromatic hydrocarbon radicals which can be substituted for R in the formula include hydrocarbon radicals having up to about carbon atoms each. Radicals having 10 carbon'atoms or less are preferred since the. resulting catalyst composition has a greater activity for initiating the polymerization of olefins. Mixtures of one or more of these organometal halide components, such 'as a mixture of ethylaluminum dichloride. and .diethylaluminum chloride, can be used in our catalyst composition. Specific examples of other organometal halides which are useful in the catalyst composition of this invention ate the following: CH AlCl (CH AlCl, z s z; 2 5)2 (C H GaF, (C H GaCl (cyclohexane derivative), (C H )GaBr (benzene derivative), C H GaBr (C H hGaF, (C H InCl (benzene derivative),

C H lnF '(C H )InBr (cyclohexane derivative) C H BeI, CH BeBr, 3-methylcyclohexylaluminum dichloride, 2-cyclohexylethylgallium dichloride; p-tolylberyllium iodide, di-(3-phenyl-l-methylpropyl)indium fluoride, 2-(3-isopropylcyclohexyl)ethylthallium dibromide, and the like;

Alternatively, or in addition to the R MX compounds set forth above, our catalyst comprises a mixture of one or more of the metal halides and one or more of the carbides and/or acetylenic compounds'described above and a mixture of an organic'halide and a free or elemental metal. .These organic halides include chloro-, bromoiodoand fiuoro-substituted organic halides, and can be mono-, di-, trior tetra-substituted organic halides. Within the broad class of organic halides which is a component of our novel catalyst composition, the class of halides defined as monohalogen-substituted hydrocarbons having a maximum carbon chain length of not greater than 8 carbon atoms are preferred since they are more easily handled in a commercial operation and are active to initiate the polymerization of olefins in the catalyst composition of this invention. Still more desirably,the organic halide which is used in the catalyst is a lower alkyl monohalide having a maximum carbon chain length of not greater than 8 carbon atoms. Examples of these organic halides which can be used in the catalyst are ethyl bromide, propyl chloride, butyl iodide and pentyl fluoride. Other examples are 1,2-dibromoethane, 1,3-dibromopropane, 1,2,3-tribromopropane, 1,2,3-trichloropropane, 1,1-

cyclopentyl chloride, l-chloro-3-phenylpropane, '1-bromo 3-phenylhexane, cyclohexyl chloride and phenyl chloride.

halide include one or more of sodium, potassium, lithium,

rubidium, cesium, beryllium, magnesium, zinc, cadmium, mercury, aluminum, gallium, indium, and thallium. The metals are usually used in the form of shavings, turnings or finely divided powder. Various mixtures or combinations of the above-mentioned organic halides and metals can be employed in the catalyst composition of this invention. 7

Alternatively, or in addition to the R MX compounds and/ or the mixture of an organic halide and a free metal, as set forth above, our catalyst comprises a mixture of one or more of the metal halides and one or more of the carbides and/or acetylenic compounds described above and a complex hydride corresponding to the formula M"M"H wherein M" is an alkali metal, including sodium, potassium, lithium, rubidium and cesium, M'. is a metal selected from the group consisting of aluminum, gallium, indium and thallium, and m is equal to the sum of the valences of the two metals. Examples of such complex hydrides are lithium aluminum hydride, potassium aluminum hydride, sodium aluminum hydride, cesium aluminum hydride, sodium gallium hydride, lithium thallium hydride, lithium indium hydride, lithium gallium hydride, rubidium aluminum hydride, and the like. The preferred member of this class of compounds is lithium aluminum hydride.

' Among the catalyst compositions falling within this disclosure which are preferred'because their use to catalyze the polymerization of olefins provides relatively high molecular weight polymers and/or permits the use of relatively low reaction temperatures and pressures are the following: a mixture of titanium tetrachloride and cuprous carbide with an approximately equimolar mixture of ethylaluminurn dichloride and diethylaluminum chloride; a mixture of zirconium tetrachloride and cuprous carbide with an approximately equimolar mixture of ethylaluminum dichloride and diethylaluminum dichloride; a mixture of titanium tetrachloride, calcium carbide and lithium aluminum hydride; a mixture of titanium trichloride and calcium carbide with an approximately equimolar mixture of ethylaluminum dichloride tion which is used in the polymerization of olefins can.

vary over a wide range. Relatively small amounts of the catalyst provide the desired activating efiect when the polymerization reaction is carried out as a batch process with continuous addition of the olefin as the polymerizae tion reaction occurs. As much as 50 to 2000 grams of polymer can be obtained per gram of catalyst composition utilized in the reaction. When a continuous flow system is, employed, the concentration of the total catalyst composition is usually in the range from 0.01 weight percent to 1.0 weight percent, or higher.

V The ratio of the amounts of carbide and/or acetylenic compound to metal halide will generally be in the range of 0.01 to 100, preferably 0.5 to 10 mols of carbide and/or acetylenic compound per mol of metal halide. The ratio of the amounts of organometal halide to metal halide will usually be in the range of 0.05 to 50, pref erably 0.2 to 3 mols of organometal halide per mol of metal halide. The ratio of the amounts of organic halide,

metal and metal halide will be in the range of 0.02 to 50 mols of the organic halide per mol of the metal halide and from 0.02 to 50 mols of the metal per mol of the metal halide. A. preferred ratio is from 0.2 to 3 mols of organic halide per mol of metal halide and from 0.2 to 3?;[1018' of metal per mol of the metal halide. The ratio with this invention can be defined broadly as polymerizable hydrocarbons. Preferably, the polymerizable hydrocarbons are olefins containing a CH =C radical. The preferred class of polymerizable hydrocarbons used is aliphatic l-olefins having up to and including 8 carbon atoms per molecule. Specifically, the normal l-olefin, ethylene, has been found to polymerize to a polymer .thereof upon being contacted with the catalyst composition of this invention at lower temperatures and pressures than'have been used in theprocesses of the prior .art mentioned above. Examples of other polymerizable hydrocarbons which can be used in the process of this invention are propylene, l-butene, l-hexene and l-octene. Branched chain olefins can also be used, such as isobutylene. Also, 1,1-dialkyl-substituted and 1,2-dialkylsubstituted ethylenes can also be used, such as butene-2, pentene-2, hexene-Z, heptene-3, Z-methyl-butene-l, 2- methyl-hexene-l, Z-ethyl-heptene-I, and the like. Examples of the diand polyolefins in which the double bonds are in non-conjugated positions and which can be used in accordance with this invention are 1,5-hexadiene,

1,4'-pentadiene and 1,4,7-octatriene. Cyclic olefins can also be used, such as cyclohexene. Mixtures of thefore- -going polymerizable hydrocarbons can be polymerized to a solid polymer in the presence of our novel catalyst as, --for example, by copolymerizing ethylene and propylene, ethylene and l-butene, propylene and l-butene, or propylene and a pentene. Aryl olefins, e. g., styrene and alkylsubstituted styrenes can also'be polymerized to a solid polymer in the process of this invention. This invention is also applicable to the polymerization of a monomeric material comprising conjugated'dienes containing from 4 to 8, inclusive, carbon atoms. Examples of conjugated dienes which can be used include 1,3-butadiene, 2 -methyl- "l,3-butadiene, 2,3-dimethyl-1,3 butadiene, 2-methyl-l,3- pentadiene, chloroprene, l-cyanobutadiene, 2,3-dimethyl- 1, 3-pentadiene, '2-methyl-3-ethyl-l,3=pentadiene, Z-meth- 'oxybutadiene, Z-phenyl-butadiene, and the like. It is within the scope of the invention to polymerize such conjugated dienes either alone or in admixture with each other and/or with one or more other compounds containing an active CH =C group which are copolymerizable therewith. Included among these latter compounds are monoolefins such as those described hereinabove. Other examples of compounds containing an active CH "=C group which are copolymerizable with one or more conjugated dienes are styrene, acrylonitrile, -methacrylonitrile, methacrylate, methyl 'methacrylate, :vinyl acetate, vinyl chloride, Z-methyl-S-vinyl-pyridirie, 2- vinylpyridine, 4-vinylpyridine, etc.

One of the important advantagesobtaincdin the polymerization of olefins in the presence of our novel catalyst is that lower temperatures and pressures can be used than 'in certain of the prior art processes. The temperature can be varied over a rather broadrange, however, such as from 250 F. and below to 500 F. and above. The preferred temperature range is from to 300 F. Al-

though pressures ranging from atmospheric and below up to 30,000 p. s. i. g. or higher can be employed, a pressure from atmospheric to 1000 p. s. i. g. is usually preferred with a pressure in the range of 100 to 700 p. s. i. g. being even more desirable.

In this connection, it is noted that it is preferred to carry out the reaction in the presence of an inert, organic diluent, preferably a hydrocarbon, with a pressure sufficient to maintain the diluent in the liquid phase, giving "rise to a so-called mixed-phase system. However, the polymerization process of this invention proceeds in the gaseous phase without a diluent. The preferred pressure r'ange set forth above has been found to'produce solid polymers of olefins in excellent yields.

tures. aromatics, halogenatedparafiins, halogenated cycloparaf- "tins and 'the like, are also useful as dilu'ents. Mixtures 'of any two or more ofthe above-named diluents can is carried out. of catalyst inactivating materials, such 'as oxygen or Suitable diluents :for. use .-in :the ;polymerization process are paraflins, cycloparaifins and/or aromatic hydrocarbons which are relatively inert, non-deleterious and liquid under the conditions of the process. The lower molecular weight alkanes, such as propane, butane, and pentane are especially useful when the process is carried out at low temperatures. However, the higher molecular weight paraflins and cycloparatfins, such as isooctane, cycloliexane and methylcycloh'exan'e, and aromatic diluent'sjsuch'as benzene, toluene and the like, can also be used, particularly when operating at, higher tempera- Halogenate'd hydrocarbons, such as halogenated also be employed in'the process this invention.

The process of this invention can be carried out as a batch process by pressuring the olefin intoa reactor containing the catalyst and diluent, if the latter is used. Also, the process can be carried out continuously by maintaining the above-described concentrations of re range: of one second to an hour or more, In'the batch process, 'the time for the reaction can also vary widely, 'suchas up to 24 hours or more.

It'hasbeenfoun d that various materials insonie instances may have 'a'tendenc'y to inactivate the catalyst :compositions of this invention. These materials include carbon dioxide, oxygen and water. Therefore, it is usually desirable to free the polymerizablehydrocarbon from these materials, "as well as from other materials which may tend to inactivate the'catalyst before contacting the hydrocarbon with the catalyst. Any of the known means for removing such contaminants can be'employed. When a diluent is used in the process, this material should generally be freed'of contaminants, such as water, oxygen, and the like. "It isdesirable, also, thatair and moisture beremoved from the reaction vessel before the reaction However, in some cases small amounts water, can be tolerated in the reaction mixture while still obtaining reasonably good polymerizationrates. his to be understood that the amount of such materials present in the reaction mixture shall not be suflicient to completely inactivate the catalyst.

At the completion of the polymerization reaction, any excess olefin is vented and the contents of the reactor, including the solid polymer swollen with diluent, are then treated to inactivate the catalyst and remove the catalyst residues. The inactivation of the catalyst can be accomplished by washing with an alcohol, water or other-suitable material. In some instances, the'catalyst inactivating treatment also removes a major proportion of the catalyst residues While in other cases it may be necessary to treat the polymer with an acid, base or other suitable material in order to efiect the desired removal of the catalyst residues. The treatment of the polymer may be carried out in a comminution zone, such as a Waring Blendor, so that a finely divided polymer is thereby provided. The polymer is then separated from the diluent and treating agents, e. g., by decantation or absorption, after which thepolym'er is dried. The diluexit and treating agents can be separated by'any suitable means, e. g., by fractional distillation, and reused'in'the process. 7

A more comprehensive understanding of the invention may be obt'ained by referring to the renewin illusundulyilimitative.

and 3 grams of calcium carbide. .gredi'ents was done under purified nitrogen. The reactor was flushed twice with ethylene and then pressured with .ethylene to 300 p. s. i. g. The reactor was heated for trafive examples which are not intended, however, to be EXAMPLE I Ethylene was polymerized in a 2700 cubic centimeter stainless steelrocking autoclave in the presence of a catalyst consisting of titanium tetrachloride, cuprous carbide and a mixture of diethylaluminum chloride and ethylaluminum dichloride. The cuprous carbide was prepared in the following manner. An aqueous solution of 1 7.15 grams of CuCl -2H O in 100 cubic centimeters of distilled water was prepared, and concentrated ammonium hydroxide was added until the odor of ammonia persisted. Hydrox ylamine hydrochloride was added until the blue color disappeared, and acetylene was introduced .untilno further precipitate of cuprous carbide formed.

The precipitate was filtered and washed three times with water, three times with n-propanol, and three times with benzene. V p Asuspension of 3.2 grams of cuprous carbide in benzene was transferred to the reactor which had been previously purged with purified nitrogen and charged with 400 cubic centimeters of benzene (distilled from sodium),

2 grams of titanium tetrachloride and 4 grams of a .rnixture of diethylaluminum dichloride. ture was prepared in accordance with the procedure de- This latter mixscribed hereinbelow. The reactor, which was flushed with purified nitrogen during charging and then with ethylene,

was closed and. rocked for ten minutes. The temperatureof the charge was 120 F. The reactor was pressured with ethylene to 300 p. s. i. g., and after one minute the temperature had increased .to .1533.F. and

and after .four minutes the temperature was 148 F.

'and the pressure was 300 p. s. i. g. The reaction mixture was heated, and in three hours and twelve minutes the temperature was 279 F. and the pressure was 195 p. s. i. g. Ethylene was again introduced to give a pres sure of 655 p. s. i. g., and after two hours and eighteen minutes the temperature was 295 F. and the pressure had dropped to 500 p. s. i. g. The reaction was stopped, and upon opening the reactor it was found that 'a solid, dark gray polymer had formed. The polymer was removed from the reactor and'comminuted in a Waring Blender with 1,000 cubic centimeters of methanol, filtered,

and dried overnight in a vacuum oven at F. The properties of a sample'of this ethylene polymer are presented'below in Table I. a

Ethylene was polymerized in a 1400 cubiccentimeter stainless steel autoclave in the presence of a catalyst consisting of titanium tetrachloride, calcium carbide, and a mixture of diethylaluminum chloride and ethylaluminum dichloride.

Thereactor was flushed with purified nitrogen and charged with 350 cubic centimeters of cyclohexane (distilled fromsodium), 2.6 grams of titanium tetrachloride, Charging of the in three hours and forty minutes during-which time the temincreased to. 715 p. s. i. :g. The reactor contents were then cooled .to 82F the ethylene was vented, and 4 grams of a mixture of diethylaluminum chlorideand ethylaluminum. dichloride was charged to the reactor under purified nitrogen. This latter mixture was prepared in accordance with the procedure described hereinbelow; The reactor was then pressured to320 p. s. i. g. with ethylene, and after five minutes the temperature had increased to 94 F. and the pressure had dropped. to 220 p. 5. i. g. The reactor was repressured with ethylene'to 350 p. s. i. g., and in another five minutes the temperature was, F. and the pressure was 240 p. s. i.' g. Thereactor was then repressured with ethylene to 600 p. s. i. g., and in another seven minutes the temperature reached 172 F. and the pressure droppedto 250 p. s. i. g. Ethylene was again introduced into the reactor until the pressure reached 600 p. s. i. g., and after three minutes the temperature was 150 F. and the pressure was 500 p. s. i. g. The last charge of ethylene wasintroduced until the pressure reached 600 p. s. i. g., and the reactor contents were heated After two hours and five minutes, the temperature was 185? F. and the pressure had dropped to 280 p. s. i. V g. The reactor was cooled and upon openingwas found to be full to the walls of the reactor. 7 The polymer was comminuted in a Waring Blendor with 1000 cubic centimeters of methanol, filtered, and dried overnight in a vacuum oven at 80 C. About grams of ethylene polymer was recovered. The polymer was insoluble in benzene, and a compression molded disc was light brown in color and had good flexibility. Other properties of this ethylene polymer are presented below in Table II.

v Table II v p Molecular weight (based on melt index) 62,000 Density, grams/cc. at room temperature 0.945 Impact strength (falling ball method) inches 72 Melt index 0.057

Melting point, F l. 2481-4 EXAMPLE III Ethylene was'polymerized in a 1200 cubic centimeter stainless steel rocking autoclave in the presence of a catalyst consisting of a mixture of 3.55 grams of titanium tetrachloride and 4 grams of a mixture of diethylalumh' num chloride and ethylaluminum dichloride. The mixture of diethylaluminum chloride and ethylaluminurn diture increased rapidly to 175 F. The ethylene was passed into the autoclave as rapidly as the limitations of the purification system would permit. 7 Maximum pressure reached in the autoclave was 300 p. s. i. g. At the end of a 15 minute reaction period, the bomb was opened, and a polymer of ethylene was present as a suspension in the benzene solution. One hundred cubic centimeters of butyl alcohol was added to the autoclave to inactivate the catalyst. The solid polymer was filtered from the benzene-alcohol mixture and then washed with isopropyl alcohol. After filtering the polymer from the isopropyl alcohol, it was dried overnight in a vacuum oven at about F. About 100 grams of polyethylene was obtained.

The properties of a sample of the ethylene polymer-produced as described above are'presentedbelow in Table The polymerization of the Table III Molecular weight (based on melt index) 9,025. Density, grams/cc. at room temperature 0.941.

Flexibility Quite brittle. Impact strength (falling ball method) Broke at 6". Melt index 445.0. Melting point, F 242:2. Inherent viscosity 0.451.

'Color Light tan.

The ethylene used in the above examples was passed through a purification system prior to charging in order to remove oxygen, carbon dioxide and water vapor. The purification system comprised a pyrogallol solution, a sodium hydroxide solution and drying agents.

The mixture of diethylaluminum chloride and ethylaluminum dichloride was prepared by placing 150 grams of aluminum shavings in a flask fitted with a reflux condenser and heated to about 70 C. A trace of iodine was added to the flask to act as a catalyst, and ethyl chloride was charged to the flask in liquid phase. The temperature of the reaction mixture was maintained in the range of 120 to 150 C. during the addition of the ethyl chloride, and the reaction mixture was maintained under a nitrogen atmosphere. When substantially all of the aluminum shavings had reacted with the ethyl chloride, the liquid product was removed from the flask and fractionally distilled at 4.5 millimeters of mercury pressure in a packed distillation column. The distillate, boiling at 72 to 74 C. at 45 millimeters of mercury pressure, was used in the catalyst compositions of Examples 1, H and III in the amount specified hereinabove. This fraction boiling at 72 to 74 C. was analyzed and found to contain 47.4 weight percent chlorine. The theoretical chlorine content for an equimolar mixture of diethylaluminum chloride and ethylaluminum dichloride is 43 weight percent.

From a consideration of the data shown in Tables I, ll and Ill, it is seen that the addition of carbides to the catalyst composition consisting of titanium tetrachloride and a mixture of diethylaluminum chloride and ethylaluminum dichloride resulted in an ethylene polymer having a higher molecular weight and possessing greatly increased impact strength.

The polymers produced inaccordance with this invention have utility in applications where solid plastics are used. They can be used to impregnate paper and fabrics, and they can be molded to form articles of any desired shape, such as bottles and other containers for liquids. Furthermore, they can be formed into pipe by extrusion.

It will be apparent to those skilled in the art that variations and modifications of our invention can be made upon study of the foregoing disclosure. Such variations and modifications are believed to be clearly within the spirit and scope of the invention.

We claim:

1. A method for polymerizing a polymerizable hydrocarbon which comprises contacting said hydrocarbon with a catalyst comprising (1) a metal halide selected from the group consisting of halides of titanium, zirconium, hafnium and germanium, (2) a compound selected from the group consisting of carbides corresponding to the formula M C and acetylenic compounds corresponding to the formula M'--(CECR') wherein M is a metal selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, magnesium, barium, strontium, calcium, zinc, cadmium, mercury, copper, silver and gold, wherein R is selected from the group consisting of hydrogen, an alkyl radical, a cycloalkyl radical, an aryl radical, and combinations of these radicals, wherein a equals 2 when the valence of metal M' is 1 and wherein a equals 1 when the valence of metal M is 2, and wherein b is equal to the valence of metal M, and (3) at least one component selected from the following: (a) an organometal halide corresponding to the formulaR MX wherein R is selected from the group consisting of a saturated acyclic hydrocarbonradical, a saturated cyclic hydrocarbon radical, an aromatic hydrocarbon radical, and combinations of these radicals, wherein M is a metal selected from the group consisting of aluminum, gallium, indium, thallium and beryllium, wherein X is a halogen, and wherein x and y are integers, the sum of x and eing equal to the valence of metal M; (b) a mixture of an organic halide and at least one metal selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, zinc, cadmium, mercury, aluminum, gallium, indium and thallium; and (c) a complex hydride corresponding to the formula M"M" H wherein M is an alkali metal, wherein M is a metal selected from the group consisting of aluminum, gallium, indium, and thallium, and wherein m is equal to the sum of the valences of the two metals M and M'.

2. A method in accordance with claim 1 wherein said polymerizahle hydrocarbon is an aliphatic l-olefin having up to and including 8 carbon atoms per molecule.

3. A method in accordance with claim 1 wherein said polymerizable hydrocarbon is ethylene and said catalyst consists essentially of a mixture of titanium tetrachloride, cuprous carbide, and an approximately equimolar mixture of ethylaluminum dichloride and diethylaluminum chloride.

4. A method in accordance with claim 1 wherein said polymerizable hydrocarbon is ethylene and said catalyst consists essentially of a mixture of zirconium tetrachloride, cuprous carbide, and an approximately equimolar mixture of ethylaluminum dichloride and diethylaluminum chloride.

5. A method in accordance with claim 1 wherein said polymerizable hydrocarbon is ethylene and said catalyst consists essentially of a mixture of titanium tetrachloride, calcium carbide, and lithium aluminum hydride.

6. A method in accordance with claim 1 wherein said polymerizable hydrocarbon is ethylene and said catalyst consists essentially of a mixture of titanium trichloride, calcium carbide, and an approximately equimolar mixture of ethylaluminum dichloride and diethylaluminum chloride.

7. A method in accordance with claim 1 wherein said polymerizable hydrocarbon is ethylene and said catalyst consists essentially of a mixture of titanium tetrachloride, calcium carbide, and an approximately equimolar mixture of ethylaluminum dichloride and diethylaluminum chloride.

8. A polymer produced in accordance with the method of claim 1.

9. A method for producing a solid polymer of an aliphatic l-olefin havin up to and including 8 carbon atoms per molecule which comprises contacting said olefin with a catalyst comprising 1) a metal halide selected from the group consisting of halides of titanium, zirconium, hafnium and germanium, (2) a compound selected from the group consisting of carbides corresponding to the formula M',,C and acetylenic compounds corresponding to the formula M'-(CECR');,, wherein M is a metal selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, magnesium, barium, strontium, calcium, zinc, cadmium, mercury, copper, silver, and gold, wherein R is selected from the group consisting of hydrogen, an alkyl radical, a cycloalkyl radical, an aryl radical. and combinations of these radicals, wherein :1 equals 2 when the valence of metal M is l and wherein a equals 1 when the valence of metal M is 2, and wherein b is equal to the valence of metal M, and (3) at least one component selected from the following: (a) an organomeal halide corresponding to the formula R MX wherein R is selected from the group consisting of a saturated acyclic hydrocarbon radical, a saturated cyclic hydrocarbon radical, an aromatic hydrocarbon radical, and combinations of these radicals, wherein M is a metal selected from the group gear A47 "consisting of aluminum, gallium, indium, thallium and beryllium, wherein X is a halogen, and wherein x and y areintegers, the sum of x and y being equal to the valence lium, and wherein m is equal to the sum of the valences of the two metals M" and M, at a temperature in the range of -250 F. to 500 F., in the presence of a hydrocarbon diluent, inert and liquid under conditions of the method at a pressure sutlicient to maintain said diluent in liquid phase, and recovering the solid polymer so produc'ed.

10. A method in accordance with claim 9 wherein the 'ratio of the amounts of the components of said catalyst are in the following ranges: from 0.01 to 100 mols of 'said carbides and said acetyleuic compound per mol of said metal halide; from 0.05 to 50 mols of said organemetal halide per mol of said metal halide; from 0.02 to 50 mols of said organic halide per mol of said metal halide and from 0.02 to 50 mols of said metal per mol of said metal halide; and from 0.05 to 50 mols of said complex hydride per mol of said metal halide.

11. A method in accordance with claim 9 wherein the ratio of the amounts of the components of said catalyst are in the following ranges: from 0.5 to l0 mols of said carbides and said acetylenic compounds per mol of said metal halide; from 0.2 to 3 mols of said organometal halide per mol of said metal halide; from 0.2 to 3 mols of said organic halide per mol of said metal'halide and from 0.2 to 3 mols of said metal per mol of said metal halide; and from 0.2 to 3 mols of said complex hydride per mol of said metal halide. a

12. A method for polymerizing ethylene which comprises contacting ethylene With a catalyst consisting essentially of a mixture of titanium tetrachloride, cuprous carbide, and an approximately equimolar mixture of diethylaluminum chloride and ethylaluminum dichloride, in the presence of a hydrocarbon diluent, inert and liquid under conditions of the method, at a temperaturein the range of 50 to 300 F., and a pressure in the range of 100 to 700 p. s. i. g. 7

13. A method for polymerizing ethylene which corn prises contacting ethylene with a catalyst consisting essentially of a mixture of titanium tetrachloride, calcium carbide, and an approximately equimolar mixture of diethylaluminum chloride and ethylalurninum dichloride, in the presence of a hydrocarbon diluent, inert and liquid under conditions of the method, at a temperature in the range of 50 to 300 F., and a pressure in the range of 100 to 700 p. s. i. g.

14. A catalyst composition comprising (1) a metal halide selected from the group consisting of halides of titanium, zirconium, hafnium and germanium, (2) a compound selected from the group consisting of carbides corresponding to the formula M C and acetlyenic compounds corresponding to the formula M(CECR') wherein M is a metal selected from the group consisting 5 of lithium, sodium, potassium, rubidium, cesium, magnesium, barium, strontium, calcium, zinc, cadmium, mercury, copper, silver and gold, wherein R is selected from the group consisting of hydrogen, an alkyl radical, a cycloalkyl radical, an aryl radical, and combinations of 19 these radicals, wherein a equals 2 when the valence of metal h is 1 and wherein a equals 1 when the valence of metal M is 2, andwherein b is equal to the valence of metal M, and (3) at least onecomponent selected rem the following: (a) an organometal halide corresponding to the formula R MX wherein R is selected from the group consisting of a saturated acylic hydrocarbon radical, a saturated cyclic hydrocarbon radical, an aromatic hydrocarbon radical, and combinations of these radicals, wherein M is a metal selected from the group consisting of aluminum, gallium, indium, thallium and beryllium, wherein X isv a halogen, and wherein x and y are integers, the sum of x and y being equal to the valence. of metal M; (b) a mixture of an organic halide and at least one metal selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, zinc, cadmium, mercury, aluminum, gallium, indium and thallium; and (c) a complex hydride corresponding to the formula MM"'H wherein M" is an alkali metal, wherein M' is a metal selected from the group consisting of aluminum, gallium, indium, and thallium, and wherein m is equal to the sum of the valences of the two metals in" and l--"'.

15. A catalyst composition consisting essentially of a' mixture .of titanium tetrachloride, cuprous carbide, and 35 an approximately equimolar mixture of ethylaluminum dichloride and diethylaluminumchloride.

16. A catalyst composition consisting essentially of a mixture of zirconium tetrachloride, cuprous carbide, and an approximately equimolar mixture of ethylaluminum dichloride and diethylaluminurn chloride.

17. A, catalyst composition consisting essentially of titanium tetrachloride, calcium carbide, and lithium aluminum hydride. v a

18. Acatalyst composition consisting essentially of a mixture of titanium trichloride, calcium' carbide, and an approximately equimolar mixture of ethylaluminum dichloride and diethylaluminum chloride.

19. The catalyst composition consisting essentially of a mixture of titanium tetrachloride, calcium carbide, and an a approximatelyequimolar mixture of ethylaluminum dichloride and diethylaluminum chloride.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A METHOD FOR POLYMERIZING A POLYMERIZABLE HYDROCARBON WHICH COMPRISES CONTACTING SAID HYDROCARBON WITH A CATALYST COMPRISING (1) A METAL HALIDE SELECTED FROM THE GROUP CONSISTING OF HALIDES OF TITANIUM, ZIRCONIUM, HAFNIUM AND GERMANIUM, (2) A COMPOUND SELECTED FROM THE GROUP CONSISTING OF CARBIDES CORRESPONDING TO THE FORMULA M''AC2 AND ACETYLENIC COMPOUNDS CORRESPONDING TO THE FORMULA M''-(C$CR'')B, WHEREIN M'' IS A METAL SELECTED FROM THE GROUP CONSISTING OF LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CESIUM, MAGNESIUM, BARIUM, STRONTIUM, CALCIUM, ZINC, CADMIUM, MERCURY, COPPER, SILVER AND GOLD, WHEREIN R'' IS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN, AN ALKYL RADICAL, A CYCLOALKYL RADICAL, AN ARYL RADICAL, AND COMBINATIONS OF THESE RADICALS, WHEREIN A EQUALS 1 WHEN THE VALENCE OF METAL M'' IS 1 AND WHEREIN A EQUALS 1 WHEN THE VALENCE OF METAL M'' IS 2, AND WHEREIN B IS EQUAL TO THE VALENCE OF METAL M'', AND (3) AT LEAST ONE COMPONENT SELECTED FROM THE FOLLOWING: (A) AN ORGANOMETAL HALIDE CORRESPONDING TO THE FORMULA RXMXY, WHEREIN R IS SELECTED FROM THE GROUP CONSISTING OF A SATURATED ACYCLIC HYDROCARBON RADICAL, A SATURATED CYCLIC HYDROCARBON RADICAL, AN AROMATIC HYDROCARBON RADICAL, AND COMBINATIONS OF THESE RADICALS, WHEREIN M IS A METAL SELECTED FROM THE GROUP CONSISTING OF ALUMINUM, GALLIUM, INDIUM, THALLIUM AND BERYLLIUM, WHEREIN X IS A HALOGEN, AND WHEREIN X AND Y ARE INTEGERS, THE SUM OF X AND Y BEING EQUAL TO THE VALENCE OF METAL M; (B) A MIXTURE OF AN ORGANIC HALIDE AND AT LEAST ONE METAL SELECTED FROM THE GROUP CONSISTING OF LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CESIUM, BERYLLIUM, MAGNESIUM, ZINC, CADMIUM, MERCURY, ALUMINUM, GALLIUM, INDIUM AND THALLIUM; AND (C) A COMPLEX HYDRIDE CORRESPONDING TO THE FORMULA M"M"''HM, WHEREIN M" IS AN ALKALI METAL, WHEREIN M"'' IS A METAL SELECTED FROM THE GROUP CONSISTING OF ALUMINUM, GALLIUM, INDIUM, AND THALLIUM, AND WHEREIN M IS EQUAL TO THE SUM OF THE VALENCES OF THE TWO METALS M" AND M"''.
 16. A CATALYST COMPOSITION CONSISTING ESSENTIALLY OF A MIXTURE OF ZIRCONIUM TETRACHLORIDE, CUPROUS CARBIDE, AND AN APPROXIMATELY EQUIMOLAR MIXTURE OF ETHYLALUMINUM DICHLORIDE AND DIETHYLALUMINUM CHLORIDE. 